1. Field of the Invention
This invention relates to a method for the separation of blood components and an apparatus therefor. More particularly, this invention relates to a method for the efficient separation of blood components such as red blood corpuscles, white blood corpuscles and platelets from whole blood, and an apparatus therefor.
2. Description of Prior Art
Hemophilia is an inherited disorder of the blood marked by a permanent tendency to hemorrhage due to the lack of the blood coagulating activity of factor VIII or factor IX. The hemophilia caused by the deficiency of factor VIII is called hemophilia A (factor VIII deficiency, classic hemophilia ) and the hemophilia caused by the deficiency of factor IX is called hemophilia B (factor IX deficiency, Christmas disease). Unfortunately, no radical therapy has yet been established for hemophilia. The conventional therapy inevitably resorted to even today consists of supplementing factor VIII to combat hemophilia A or factor IX, hemophilia B, as occasion demands. When a patient with hemophilia has a hemorrhage, the deficient coagulation factor is administered with minimum loss of time. When the patient has to undergo a surgical operation or a dental treatment, this supplementation is to be made in advance of the operation or treatment. The factor VIII is unstable and loses activity during storage. Thus, the supplementation of factor VIII necessitates the use of fresh blood. The factor IX is so stable that the supplementation may be effected by use of preserved blood. When the whole blood or the blood plasma is used, an ample supply of a coagulation factor is obtained with great difficulty. The intravenous injection of a concentrated preparation such as a cryoprecipitate, Cohn fraction I, or a concentrated factor VIII for the factor VIII or that of a refined prothrombin for the factor IX has found popular acceptance.
In the preparation of factor VIII, the concentrated preparation of factor VIII is obtained by highly concentrating the factor VIII. The recovery of this concentrate is only about 20% because the coagulating activity of the factor VIII is degraded during the course of the concentration. Further since the blood plasma used as the raw material for this preparation is collected from many donors, the possibility of viruses such as those responsible for hepatitis contaminating the preparation is high. In contrast, the cryoprecipitate is prepared by a simple and convenient procedure from the blood plasma collected from a small number of donors and, therefore, the possibility of viruses contaminating the product is low. Moreover, the recovery of the coagulating activity of the factor VIII is high. Since this preparation is obtained by concentration of a limited extent, however, it has a large liquid content and contains fibrinogen and other extraneous proteins in a large proportion. When it is transfused in a large amount, therefore, it has the possibility of increasing the amount of blood plasma for circulation, elevating the concentration of fibrinogen, and inducing secondary reactions such as hemolysis.
Heretofore, separation of a blood sample into red blood corpuscles, white blood corpuscles, platelets, and various other components has been effected by various operations performed with a blood component separation device as illustrated in FIG. 10, for example. In the blood separation device, a blood component transferring tubular member 4 is attached to a blood collecting bag (parent bag) 3 which is provided with a blood introducing tubular member 2 having a vial needle 1 connected to the leading end thereof. The tubular member 4 is connected to a third satellite bag 5 and, at the same time, joined through a first branching tube 6 and a first liquid separating tube 7 to a first satellite bag 8 and also joined through a second branching tube 9 and a second liquid separating tube 10 to a second satellite bag 11.
In the separation of blood into the components thereof by the use of the blood component separation device configuration as described above, when the whole blood collected from the blood vessel such as, for example, the vein into the blood collecting bag 3 is subjected to weak centrifugation, it is separated into a layer of platelet-rich blood plasma (PRP) and a mixed layer of white blood corpuscles (LC) and concentrated red blood corpuscles (CRC). After the upper PRP layer has been transferred to the first satellite bag 8, the blood component transferring tubular member 4 is separated and the mixed layer remaining in the blood collecting bag is used for blood transfusion with the LC left intact therein. The PRP in the first satellite bag 8 is subjected to strong centrifugation so as to transfer the platelet-deficient blood plasma (PRP) in the upper layer to the second satellite bag 11. The platelet concentrate (PC) which remains in the first satellite bag 8 is pelletized and then allowed to float again in the plasma to produce a platelet preparation. The PPP which has been transferred to the second satellite bag 11 is frozen, thawed, and centrifuged to obtain a cryoprecipitate (AHG). This cryoprecipitate is further centrifuged and the cryoprecipitate-deficient blood plasma (CRP) which occurs as a supernatant is transferred to the third satellite bag 5.
In the method described above, however, since the white blood corpuscles are not specifically separated, the white blood corpuscles which are wholly contained in the red blood corpuscles are simultaneously transfused when the red blood corpuscles are to be transfused. If the white blood corpuscles (lymphocytes) happen to contain adult T cell originated hemophilia antibody (ATLA), the transfusion has entailed the possibility of infecting the patient under treatment with the hemophilia. The ATLA has a long latent period and the patient holding this antibody is not conscious and unaware of any symptom unless the disease manifests itself. There has been a possibility that the patient will unconsciously donate his blood and cause the aforementioned trouble of infection.
An object of this invention, therefore, is to provide a novel method for the separation of blood into the components thereof and an apparatus used for working the method.
An another object of this invention is to provide a method for the separation of blood into the component thereof without any fear of ATLA infection and an apparatus used for working the method.
A further object of this invention is to provide a method for the separation of blood into the components thereof, which method is capable of separating the blood into individual components independently of each other in a closed system and an apparatus for working the method.